A VISUAL STUDY OF THE FLOW AROUND AN OSCILLATING CIRCULAR CYLINDER AT LOW KEULEGAN-CARPENTER NUMBERS AND LOW STOKES NUMBERS

The structures of the flow induced by a circular cylinder performing sinusoidal oscillations in a fluid at rest are investigated by means of flow visualisation. The experiments are carried out at Keulegan-Carpenter numbers between 1.6 and 15 and at Stokes numbers between 5 and 160. Above a certain value of Keulegan-Carpenter number, depending on the Stokes number, some asymmetry appears in the flow separation and the associated vortex development behind the cylinder. The two vortices which are developed in a half cycle differ in strength and may be convected in different directions. This results in a fascinating set of flow patterns. Eight different regimes of flow can be identified within the ranges of Keulegan-Carpenter number and Stokes number studied. Furthermore, most of the resulting flows show a three-dimensional instability along the axis of the cylinder. Measurements of the wavelength of these disturbances are presented.

• Supplemental Notes:
  • J. Fluid Mechanics, 211 (1990) p.157 (Feb.) [26 p., 13 ref., 33 fig.]
• Authors:
  • Tatsuno, M
  • Bearman, P W
• Publication Date: 1990

Language

• English

Subject/Index Terms

• TRT Terms: Cylindrical bodies; Flow visualization
• Subject Areas: Marine Transportation; Materials;

Filing Info

• Accession Number: 00697327
• Record Type: Publication
• Source Agency: British Maritime Technology
• Files: TRIS
• Created Date: Aug 14 1995 12:00AM